perpendicular

Derived from Middle French perpendiculaire, from Old French perpendiculer, from Latin perpendiculum (“plumb line”).

der+

(obsolete, slang) A meal eaten at a tavern bar while standing up.


angle

From Middle English angle, angul, angule, borrowed from Middle French angle, from Latin angulus, anglus (“corner, remote area”). Cognate with Old High German ancha (“nape of the neck”), Middle High German anke (“joint of the foot, nape of neck”). Doublet of angulus and ankle.

cog

(astrology) Any of the four cardinal points of an astrological chart: the Ascendant, the Midheaven, the Descendant and the Imum Coeli.


right angle

(geometry) Half of the angle formed by a single straight line, equivalent to 90 degrees.


degree

From Middle English degre, borrowed from Old French degré (French: degré), itself from Latin gradus, with the prefix de-.

Appendix:Roget MICRA thesaurus/Class I § 26. Degree

Appendix:Roget MICRA thesaurus/Class I § 31. Greatness

Appendix:Roget MICRA thesaurus/Class I § 32. Smallness

She has two bachelor's degrees and is studying towards a master's degree.

(education) A stage of proficiency or qualification in a course of study, now especially an award bestowed by a university/college, as a certification of academic achievement. (In the United States, can include secondary schools.)


steradian

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International System of Units
International System of Units

(geometry) In the International System of Units, the derived unit of solid angle; the solid angle subtended at the centre of a sphere of radius r by a portion of the surface of the sphere that has area r². Symbol: sr


radian

(geometry) In the International System of Units, the derived unit of plane angle: the angle subtended at the centre of a circle by an arc of its circumference equal in length to the radius of the circle. Symbol: rad.


gradian

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(geometry, trigonometry) A unit of angle equal to 0.9 degree, so that there are 100 gradians in a right angle.


angular

en-adj

angular (comparative more angular, superlative most angular)

more angular (comparative)
most angular (superlative)

From Middle English angular, anguler, from Latin angulāris, from angulus (“angle, corner”). See angle.

an angular figure

In overall appearance, katakana symbols are more angular in shape and hiragana are more rounded. Here are the first five sounds of each script (a, i, u, e, o). Compare these two sets of symbols and see if you can identify these features:
Hiragana あ い う え お
Katakana ア イ ウ エ オ

2008, Helen Gilhooly, chapter 1, in Complete Japanese, →ISBN, page 31:

ъглест

relating to or forming an angle; sharp-cornered


acutangular

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normal

normal (comparative normaler or more normal, superlative normalest or most normal)

normaler (comparative)
more normal (comparative)
normalest (superlative)
most normal (superlative)

From Latin normālis (“made according to a carpenter's square; later: according to a rule”), from nōrma (“carpenter's square”), of uncertain origin; doublet of normale. The earliest meaning of the word in English was "perpendicular; forming a right angle" like something normālis (“made according to a carpenter's square”), but by Late Latin normālis had also come to mean "according to a rule", from which modern English senses of the word derive: in the 1800s, as people began to quantitatively study things like height, weight and blood pressure, the usual or most common values came to be called "normal", and by extension values regarded as healthy or desirable came to be called "normal" regardless of their usuality.

der

According to norms or rules or to a regular pattern.

(mathematics) Adhering to or being what is considered natural or regular in a particular field or context:

(linear algebra, of a matrix) Which commutes with its conjugate transpose.


orthogonal

/ɔːˈθɒɡ.ə.nəl/

/ɔɹˈθɑɡ.ə.nəl/

By surface analysis, ortho- + -gon + -al. From French orthogonal, in turn from Medieval Latin orthogōnālis and Latin orthogōnius (“right-angled”), ultimately from Ancient Greek ὀρθογώνιος (orthogṓnios, “rectangular”).

der

A chord and the radius that bisects it are orthogonal.

(geometry) Of two objects, at right angles; perpendicular to each other.

The normal vector and tangent vector at a given point are orthogonal.

Of a pair of vectors: having a zero inner product; perpendicular.

Of a linear transformation: preserving its angles.

Of grid graphs, board games and polyominoes: vertical or horizontal but not diagonal.


mil

An angular mil, a unit of angular measurement equal to ¹⁄₆₄₀₀ of a complete circle. At 1000 metres one mil subtends about one metre (0.98 m). Also ¹⁄₆₀₀₀ and ¹⁄₆₃₀₀ are used in other countries.


solid angle

(geometry) The three-dimensional analog of an angle, equivalent to the area of that portion of the surface of a unit sphere that it subtends.


acute-angled

(trigonometry) Of a triangle: having three acute angles.


angle bisector

A ray that divides an angle into two equal parts.


plane angle

en-noun

plane angle (countable and uncountable, plural plane angles)

(geometry) An angle formed by two intersecting straight lines.

rovinný úhel

(geometry) An angle formed by two intersecting planes, measured by the angle between two intersecting straight lines that are in respective planes and perpendicular to the intersection of the planes.


angular mil

(military) A unit of angular measurement equal to 1/6400 of a complete circle. At 1000 metres one mil subtends about one metre (~0,98 m). Also 1/6000 and 1/6300 are used in other countries.


milliradian

An SI unit of plane angular measure equal to one thousandth of a radian


microradian

A unit of angle equal to one millionth of a radian.


acute angle

(geometry) An angle measuring less than 90 degrees.

زَاوِيَة حَادَّة

angle measuring less than ninety degrees


angular defect

Prop. XVI. If the angular defects of two triangles are equal, the areas of the triangles are equal.

1864, Transactions of the Royal Society of Edinburgh, volume 23, page 444:

We have seen that under any reasonable definition of area, the angular defect of a triangle is proportional to its area.

1995, Arlan Ramsay, Robert D. Richtmyer, Introduction to Hyperbolic Geometry, page 120:

In hyperbolic geometry, similar triangles do not exist and the area of a triangle is directly proportional to its angular defect[…].

1998, Kappa Mu Epsilon, The Pentagon: A Mathematics Magazine for Students, page 7:

(geometry, non-Euclidean geometry) The amount by which the sum of the interior angles of a triangle is less than 180° (π radians); the amount by which the sum of the internal angles of a polygon is less than what would be expected on the Euclidean plane.

angular deficiency

amount by which the total of the interior angles of a polygon is less than on the Euclidean plane


circular angle

(geometry) An angle that defines a position on a circle.


hyperbolic angle

hyperbolic angle (plural hyperbolic angles)

(geometry) An angle that describes a position along a hyperbola.


base angle

(trigonometry) Either of the two angles that intersect with the base of a triangle.


square degree

(geometry) A unit of solid angle equal to π²/32400 steradian